Tetraisocyanate compositions

ABSTRACT

Selected tetrafunctional methylene-bridged aromatic isocyanates and a method for their preparation are disclosed. The utility of these isocyanates as cross-linking agents for polyurethanes is also disclosed.

Unite States Patet [191 Schnabel et al.

[451 Sept. 9, 1975 TETRAISOCYANATE COMPOSITIONS [75] Inventors: WilhelmJ. Schnabel, Branford;

Ralph A. Colafati, III, New Haven,

[21] Appl. No.: 416,043

[52] US. Cl..... 260/453 AM; 252/182; 260/25 AT;

260/453 AR; 260/453 P [51] Int. Cl. C07C 119/048 [58] Field of Search260/453 AR, 453 AM [56] References Cited UNITED STATES PATENTS 3,255,2266/1966 McShane, Jr. 260/453 Primary Examiner-Lewis Gotts AssistantExaminerDolph H. Torrence Attorney, Agent, or FirmF. A. lskander; T. P.ODay 5 7 ABSTRACT Selected tetrafunctional methylene-bridged aromaticisocyanates and a method for their preparation are disclosed. Theutility of these-isocyanates as crosslinking agents for polyurethanes isalso disclosed.

4 Claims, No Drawings TETRAISOCYANATE COMPOSITIONS This inventionrelates to a select group of tetrafunctional methylenebridged aromaticisocyanates and to a method for preparing them. The invention alsorelates to the use of these tetrafunctional isocyanates as cross linkingagents in the production of polyurethanes.

A variety of aromatic polyisocyanates has been known in the art. Theseinclude for example toluene diisocyanate and the polymeric isocyanates,e.g., polyphenylene polymethylene isocyanate, both of which have beenused extensively in the production of polyurethane foam. A further groupof such isocyanates is disclosed in US. Pat. No. 3,255,226 which relatesto a Friedel-Crafts catalyzed condensation reaction involving anaromatic isocyanate having a haloalkyl substituent and selectedsubstituted benzenes. This patent also indicates that in this type ofreaction, a small portion of the specified substituted benzenes maycondense with two moles of the haloalkyl-substituted aromaticisocyanate.

In the general art of polyurethane foam production, it is known thathigh resilience flexible foams can be prepared from a reaction mixturecomprising selected high-molecular-weight polyols and preferablyspecified mixtures of toluene diisocyanate and a polymericpolyisocyanate. It is also known in this particular art to includecertain agents in the foam forming reaction mixture. The desirability ofusing a curing agent stems from the fact that, along with acceleratingthe curing rate of the foam, it also enhances its physical properties.

To date, the most commonly used curing agents have been the aromaticdiamines, particularly the chlorinated aromatic diamines. However, dueto their high degree of toxicity, these curing agents have become highlyundesirable from an ecological standpoint. In fact, recent federalgovernment regulations have prohibited or restricted the use of severalof the most prominent such curing agents. Thus a need exists in the artfor new curing agents which, while having reduced or no toxicity, canserve as viable substitutes for the chlorinated aromatic diamines.

Now, in accordance with the invention, a new curing agent has been foundwhich is identified as bis(- diisocyanatobenzyl)-chlorobenzene. Thisnovel compound of the invention, along with being practically non-toxic,has been found to be a highly effective curing agent in the productionof polyurethanes, particularly high resilience polyurethane foam.Further according to the invention, a selective process has been foundfor the optimized production of bis(- diisocyanatobenzyl)-chlorobenzene.

The novel compound of the invention can be a single isomer or a mixtureof isomers represented by formula I as follows NCO C1 NCO NCO It isprepared, according to the method of the invention, by condensing. inthe presence of a FriedelCrafts NCO catalyst, two moles ofachlorotoluene diisocyanate with one mole of monochlorobenzene. In thecourse of this reaction, a substantial proportion of theoz-chlorotoluene diisocyanate condenses with the monochlorobenzene in a1:1 molar ratio to form diisocyanatophenyl-chlorophenyl-methane. Thus,as illustrated by the following reaction scheme, the product of thecondensation of a-chlorotoluene diisocyanate with monochlorobenzenecomprises, along with evolved hydrogen chloride, a mixture of twoisocyanates:

Nco Quip.

01 NCO NCO I Qua -Q act NCO C1 In carrying out the above-illustratedcondensation reaction, any oz-chloro-toluene diisocyanate isomer, ormixture of isomers, may be employed. Illustrative area-chloro-2,4toluene diisocyanate, a-chloro2,6-toluene diisocyanate,a-chloro-2,5-toluene diisocyanate, a-chloro-3,5-toluene diisocyanate,and mixtures thereof. However, for reasons of economy and commercialavailability, it is preferred to employ a-chloro- 2,4-toluenediisocyanate, a-chloro-2,6-toluene diisocyanate or a mixture thereof.The latter is most preferred particularly the mixture of about by weightof achloro-2,4-toluene diisocyanate and about 20% of achloro-2,6-t0luenediisocyanate.

Any Friedel-Crafts type catalyst may be employed in carrying out thecondensation reaction. This includes, for example, aluminum chloride,ferric chloride, zinc chloride, stannic chloride, and the like, aluminumchloride and ferric chloride being preferred. The catalyst may be usedin any suitable proportion, such as from about 0.1 to about 4, andpreferably about 0.4-2, parts per every parts by weight of totalreactants which are employed in preparing thebis(diisocyanato-benzyl)-chlorobenzene.

Any molar ratio of monochlorobenzene to achloro toluene diisocyanate maybe employed. However, it is preferred to employ the minimum possiblenumber of moles of monochlorobenzene per each mole of theachloro-toluene diisocyanate. This is in order to maxi- 3 mize the yieldof bis(diisocyanatobenzyl)-chlorobenzene and correspondingly reducediisocyanatophenyl-chlorophenyl-methane. Thus preferably no more thanabout moles, and more preferably at most 5 moles, of themonochlorobenzene are employed per mole of the oz-chloro-toluencdiisocyanate.

Furthermore, pursuant to the most preferred embodiments of theinvention, from'about 1.8 to about 4 moles of the monochlorobenzene areemployed per mole of the a-chlorotoluene diisocyanate.

The condensation reaction'is usually carried out at any suitabletemperature provided this is below the temperature at which the reactionproduct undergoes decomposition or which temperature will result inundesirable boil-up of the reactive mixture. Thus at atm'osphericpressure a reaction temperature of about 50135C, and preferably about9013'0C, is used. The reaction is usually completed in about 1l2 hoursas evidenced by the cessation of by-product HCl evolution. At thispoint, the excess monochlorobenzene is removed by distillation. Thealuminum chloride is precipitated out by any suitable method, and it isremoved by filtration along with any other solid matter that may bepresent. The remaining product will be a liquid blend or solution ofbis(diisocyanatobenzyl)chlorobenzene anddiisocyanatophenyl-chlorophenyl-methane. Separation of these twocompounds and recovery of the bis(diisocyanatobenzyl)-chlorobenzene canthen be achieved using conventional distillation methods.

However, in accordance with one preferred embodiment ,of .the invention,the blend vof bis(- diisocyanatobenzyl ),-chlorobenzene anddiisocyanatophenylchlorophenyl-methane is not separated. Rather it isused as such thereby doing away with the costly separation operation;for, according to the invention, it has been found thatthe'effectiveness of the bis(- diisocyanatobenzyl)-chlorobenzene, as acuring agent in polyurethanes, is not diminished or adversely affectedby the presence therewith of diisocyanatophenyl chlorophenyl-methane. Infact; to the extent that it is a low-viscosity liquid. this dissocyanateis a desirable component which acts as a solvent for the bis(diisocyanatobenzyl)-chlorobenzcne. Its presence therefore makes for easyprocessing and mixing of the bis(diisocyanatobeniyl)-chlorobenzene withthe polyurethane forming. reaction mixture;

The method of the invention enables the preparation ofbis(diisocyanatobenzyl )-'chloroben2ene is unexpectthe yield of edlyhigh yields; for unlike'other'substituted benzenes,

monochlorobenzene, when reacted with a-chloro-tol- 4 polyether triol, anorganic isocyanate, or blend of organic isocyanates, a foamingagent anda reaction catalyst. Either the one-shot method or the so-calledprepolymer technique may be used in carrying out the foaming reaction,although the one-shot method is preferred.

The select polyether triol which is used is characterized by 1 amolecular weight of at least about 4,400, (2) a trifunctional alcoholnucleus, (3) polyoxypropylene chain segments attached at one end thereofto the nucleus and (4) polyoxyethylene chain segments attached at oneend thereof to the polyoxypropylene chain segments, with the provisothat the resulting polyether contains no less than about 7, and no morethan about 18 moles of ethylene oxide per each mole of trifunctionalalcohol. This polyether can be prepared by methods generally well knownin the art wherein a trifunctional alcohol initiator .is sequentiallycondensed, in the presence of an alkaline catalyst. first with propyleneoxide and then with ethylene oxide.

The alcohol initiator used in preparing the polyether triol can be anycompound having three hydroxyl terminal groups. However, the aliphatictriols are preferred, particularly those containing 3-12 carbons.lllustrative are glycerol, trimethylolpropane, triethylolpropane,1,3,5-hexanetriol, l,2,6-hexanetriol. 1,4,6- octanetriol, and1,5,lO-dodecane triol. In accordance with the most preferred embodimentof the invention, aliphatic triols having 36 carbon atoms-are employedsuch as glycerol and trimethylolpropane. I

'While as indicated above any polyether triol. as described above, maybe employed 'in'preparing the polyurethane foams of the invention, itis'preferred to use those polyether triols which have a molecular weightof about 5,7007,000 and still more preferably about 5,8006,600. It isalso preferred thatthe ethylene oxide content in the polyether triolrange from about 12 to about 17, and more preferably from about 14 toabout 16 moles per each mole of trifunctional alcohol.

In preparing the high resilience polyurethane foam, any suitable'organicisocyanate or mixture of isocyanates may be used. It is preferredhowever to employ toluene diisocyanate, such as the 80/20 weight mixtureof the 2,4-/2,6-isomers, or a selected mixture of toluene diisocyanateand a polymeric 'isocyanate such as the polyphenylene polymethyleneisocyanates described in U.S. Pat. No. 2,683,730. The entire disclosureof this patent .is incorporated by reference herein. Where a mixture oftoluene diisocyanate and a polymeric isocyanate is used, this usuallyhas a weight ratio, toluene uene diisocyanate, has been found to yielda'surprisingly high proportion of product representing the condensationof two moles of a-chloro-toluene' diisocyaagent of the invention.Usuallysuch foams are pre' pared from a reaction mixture comprised ofa'select diisocyanatezpolymeric isocyanate, ranging from about 72:25 toabout 96:4 and preferablyfrom about 15 to about 94:6. 1n the mostpreferred embodiment of the invention, the weight ratio of toluenediisocyanate t0 the polymeric isocyanate ranges from at about 87:13 toabout 92:8. The ratio of NCO to OH groups, in the foam forming reactionmixture, multiplied by is referred to as the index.

The amount of isocyanate or mixture thereof that is employed shouldgenerally be sufficient to provide at least 0.7, NCOfgroup per hydroxylgroup in the reaction system, which includes the polyether triol as wellas any additional material and/or foaming agent present in the systemflnpractice such a proportion of isocyanate is employed as to provide nomore than 1.25, and preferably about 0.9 1.15' NCO groups per eachhydrox'yl group.

The polyurethane foams of the invention are prepared in the presence ofbis(diisoeyanatobenzyl)- chlorobenzene curing agent. While any suitableadditive arrp unt of this curing agent may be employed, it is preferredto employ relatively small amounts such as about 0.5-5.0 and preferablyabout 1-4.0, parts per 100 parts by weight of the polyether triol. Thisis in order to preclude any adverse effects which might result fromusing too much or too little curing agent. According to the mostpreferred embodiment of the invention, the curing agent is used in aproportion of about 1.6-2.4 parts per 100 parts by weight of thepolyether triol.

As indicated above, it is preferred to employ the bis(diisocyanatobenzyl)-chlorobenzene as a mixture or solution thereof indiisocyanatophenylchlorophenylmethane. Such use not only accomplishes asubstantial saving is not having to separate these two materials whichare simultaneously formed in the condensation of a-chloro-toluenediisocyanate with chlorobenzene, but it also provides the addedadvantage that, as such, the blend is a liquid material of lowviscosity. Therefore, it is easier to process and admix with other foamforming reactants than is the bis(diisocyanatobenzyl)- chlorobenzenealone. Any such blend may be employed, provided it contains at least byweight of the bis(diisocyanatobenzyl)chlorobenzene. However, as a matterof economy and convenience, it is preferred to employ the blends whichare directly obtained from the reaction described above. Such blends,according to the invention, usually have a weight ratio, bis(-diisocyanatobenzyl)chlorobenzenezdiisocyanatophenyl-chlorophenyl-methane,ranging from about :85 to about 60:40, and preferably about 25:75 toabout 50:50. Such blends have been found to be eminently suitable across-linking agents for flexible, high resilience polyetherpolyurethane foam.

Where a blend of bis(diisocyanatobenzyl)-chlorobenzene anddiisocyanatophenyl-chlorophenylmethane is used, a sufficient proportionthereof is employed as to provide the required amount of bis(-diisocyanatobenzyl)chlorobenzene which is specified above.

In preparing the polyurethane foams of the invention any suitablefoaming agent, or mixture of forming agents, may be employed. Theseinclude inorganic foaming agents such as water and organic foamingagents containing up to seven carbon atoms such as the halogenatedhydrocarbons and the low molecular weight alkanes, alkenes, and ethers.Illustrative organic forming agents include monofluorotrichloromethane,dichlorofluoromethane, dichlorodifluoromethane, l, l ,2trichloro l,2,2-trifluoroethane, methylene chloride, chloroform, carbontetrachloride, methane, ethane, ethylene, propylene, hexane, ethyl etherand diisopropyl ether. Water and the low molecular weightpolyhalogenated alkanes, such as monofluorotrichloromethane anddichlorodifloromethane, are preferred. The amount of foaming agent maybe varied within a reasonable wide range as is well known in the art.Generally however. the halogenated alkanes, for example, are employed inan amount of about 2-20, parts per 100 parts by weight of the polyethertriol which is used in making the foam; and water is employed in anamount of about l-6, and preferably about l.5-4.5, parts per 100 partsof polyether triol.

The polyurethane foams of the invention are prepared in the presence ofa catalytic amount of areaction catalyst. The catalyst employed may beany of the catalysts known to be useful for this purpose, or mixturesthereof, including tertiary amines and metallic salts, particularlystannous salts. Typical tertiary amines include, but are not limited to,the following: N-methyl morpholine, N-hydroxyl-ethyl morpholine,triethylene diamine, bis(2-dimethylaminoethyl)ether, triethylamine andtrimethylamine. Typical metallic salts include, for example, the saltsof antimony, tin and iron, e.g., dibutyltin dilaurate, stannous octoate,and the like. ln accordance with a preferred embodiment of theinvention, a catalyst comprised of an amine, such as triethylene diamineand a stannous salt, such as stannous octoate, is employed. Anycatalytic proportion of catalysts may be employed, such as about 0.04and about 1.5, and preferably between about 0.05 and about 0.75 percentby weight based on the total weight of the polyether triol which is'usedin preparing the foam.

It is preferred in the preparation of the polyurethane foams of theinvention to employ minor amounts of certain surfactants in order tofurther improve the cell structure of the polyurethane foam. Suitablesuch surfactants, include the silicones and the siloxane-oxyalkyleneblock copolymers, all of which are commercially available materials.Generally up to 2 parts of the siloxane copolymer or up to 0.1 parts ofthe silicone are employed per every parts by weight of the polyethertriol.

In the practice of this invention, a polyurethane foam-forming reactionmixture comprising the abovedescribed ingredients is fed to a suitablereaction Zone such as by pouring into a suitable mold or onto a movingconveyor belt where reaction proceeds. The foaming reaction isexothermic, and auxiliary heat is usually not necessary to effect thereaction, although it may be employed. After the reactants have beenadmixed for a period of between about 0.1 and about 20 seconds, anemulsion or cream forms. As the temperature increases from the reaction,gas bubbles are generated bringing about the formation of an uncuredcellular gel material which usually cures fairly rapidly at roomtemperature. Once cured, the foam will be ready for use in variouscushioning applications.

Polyurethane foams prepared according to the process of the inventionare characterized by a unique and highly desirable combination ofphysical properties. Ranging in density from about 1.8 to about 3.8, andpreferably from about 2.2 to about 3.0, pounds per cubic foot, they havea SAC factor generally in excess of 2.4 and usually at least 2.7. TheSAC factor" is a measure of support provided by a cushioning material.In accordance with the test described in ASTM D- l564-64T, it isexpressed as the ratio of indentation load deflection, lLD, at 65percent to 25 percent deflection. Thus by having a SAC factor of over2.4, the foams of the invention, while being quite flexible and soft atthe surface, exhibit little or no tendency to bottom out; and thisproperty is achieved in the foams of the invention in the absence offillers or other expedients which might after the basic properties ofthe foam.

The polyurethane foams 0f the invention are also endowed withsubstantially the same desirable physical properties that characterizeprior art high resilience polyurethane foams. For example, they havehigh ball drop resilience properties and improved tensile and tearstrength. In addition, these foams exhibit relatively little change inphysical properties when subjected to 7. accelerated heat or humidaging. g

Furthermore, foams prepared according to the invention are characterizedby good elongation, tensile and tear strength, and high ball dropresilience, i.e., over 45 percent as determined by the test described inASTM 68.6:3 1.4. The product was a liquid. stable for several D-l56464T.They also exhibit a sufficient degree ofmonths, having a surprisinglylow viscosity, at 25C, of resistance to burning such as to meet therequirements 216 cps. of the Motor Vehicle Safety Standard Test No. 302.This test is described in the Jan. 8, 1971 issue of the EXAMPLES 2-9 TheFederal Register, Volume 36, No. 5, beginning on The identical procedureof Example 1 was followed page 289. in carrying out these examplesexcept that different and By virtue of the combination of desirablephysical varying proportions of the monochlorobenzene were propertiescharacterizing the polyurethane foams of used such as to provide a molarratio, momochlorbenthe invention, these foams meet the rigid requirementzenezoz-chloro-toluene diisocyanate, which varied from set by theautomotive industry for making molded auto 10:1 to 2:1. In the case ofeach of these examples, the seats. They are also of utility in numerousother cushreaction product was found to contain a mixture of ioningapplications such as in the manufacture ofpaddiisocyanatophenyl-chlorophenyl-methane and -bis(- ding, seatcushions and the like. diisocyanatophenyl)-chlorobenzene. The molarratios The following examples are provided to illustrate the ofreactants and the constitution of the product is given invention. Inthese examples, all parts and percentages in Table 1 below. are byweight unless otherwlse specified. COMPARISONS l 5 EXAMPLE 1 Theidentical procedure of Examples 1-5 was re- In a reaction vessel,equipped with a thermometer, a peated, except that instead of thechlorobcnzene reacreflux condenser, a gas inlet tube and a droppingfuntant, isocyanatobenzene was used. The product of each nel, there wereplaced 1688.4 grams (15 moles) of of these comparisons was shown by GPCto be a mixmonochlorobenzene and 6.7 grams of aluminum chloture ofdiisocyanatophenyl-isocyanatophenyl-methane v ride. Then there weregradually added, over a period of andbis(diisocyanatobenzyl)isocyanatobenzene. The about 2.4 hours, 626 grams(3 moles) of a-chloro-tolmolar ratios of reactants used in thesecomparisons and uene diisocyanate which consisted of 80% by weight thecompositions of the resulting products are provided achloro-2,4-toluenediisocyanate and 20% a-chloro in Table I below.

TABLE 1 8 areas indicated that the reaction product contained 1difunctional diisocyanatophenyl-chlorophcnylmethane and (2)tetrafunctional bis(diisocyanatobenzyl)-chlorobenzene, in a weightratio, 1 ):(2), of

Condensation Reactions Involving a-Chloro-TDI & Substituted BcnzenesReactants Data Product Ana1ysis grams) Substituted Benzene Used MolarRatio 1:1 Mole Condensatef' 2:1 Mole Condensate Example 1 chlorobenzenc5:1 68.6 31.4 Comparison 1 isocyanatobcnzcne 5:1 84.1 1.5.9 Example 2chlorobenzene 10:1 78.0 22.0 Comparison 2 isocyanatobenzene 10:1 92.37.7 Example 3 chlorohenzene 4:1 (14.3 35.7 Comparison 3 isocyanatohcnzene 4:1 81.1 18.) Example 4 chlorobenzene 3:1 58.5 41 .5Comparison 4 isocyanatohcnzene 3:1 768 23.2 Example 5 chlorohenzcne 2:149.1 50.) Comparison 5 isocyanatohenzene 2:1 69.2 30.8

"Molar ratio of substituted benzene to xchloro-TD1 used.

ln thc case of each of Examples l--5, this condensate isdiist)cyanatophenyl-chlorophenyl-n'lethunc; and in the case of each ofComparisons 15, this condensate is diisocvanatophcnl-isocyanatophcnyl-mcthanc. un l diisocyanatohcnlyl l-isocyanatohcnzcnc.

2,6-toluene diisocyanate. During the addition and until completion ofthe reaction, the temperature inside the reaction vessel was maintainedwithin 120l 30C and a slow stream'of dry nitrogen gas was passed throughthe reaction mixture. The effluent nitrogen gas, which was laden withevolved HCl was passed into a water vessel where the HCl was captured byabsorption and eventually total evolved HCl was determined by titrationwith base. In the course of the reaction, an additional amount of 13.4grams aluminum chloride was added.

Upon completion of the reaction, as evidenced by the cessation of HClevolution, substantially all of the excess monochlorobenzene was removedby vacuum distillation. The remaining reaction product mixture wasanalyzed by gel permeation chromatography (GPC). The chromatogram showedtwo sharp peaks and some tailing. The positions of the peaks, comparedto a calibration curve, and computer integration of the peak asc of eachof Examples 1-5. this condensate isbis(diisocyanatohcnvyl)chlorobcnzcnc; and in the cast: of each ofComparisons l 5, this condensate is bis(- The data in Table 1demonstrates the unexpectedly high tendency of monochlorobenzene tocondense with two moles of a-chloro-toluene diisocyanate as cornparedwith the same type of condensation reaction'involving a-chlorotoluenediisocyanate and another prior art substituted benzene, namely,isocyanatobenzene. Inasmuch as this result is shown to obtain at variouslevels of reactants molar ratio, it demonstrates the surprisingimprovement provided by the invention for preparingbis(diisocyanatobenzyl)-chlorobenzene.

COMPARISON 6 For further comparison purposes, Example 3 was repeatedexcept that instead of the monochlorobenzene reactant, toluene was used.The product was confirmed by GPC to be a mixture of 86.1% by weight ofdiisocyanatophenylmethylphenyl-methane and 13.9% by weight of bis(diisocyanatobenzyl)toluene.

EXAMPLE 6 The amount of 7.5 grams of the product of Example 1 (which isequivalent to 2.36 grams of the bis(- diisocyanatobenzyl)-chlorobenzeneof the invention) was used as a curing agent in preparing a flexiblepolyurethane foam from the following ingredients in the indicatedproportions:

ingredients Grams Polyether triol" 100.0 Water 3. 1 Catalyst systemtriethylene diamine 0.4 bis( Z-dimethylaminoethyl )ether 0.04 stannousoctoate 0.02 Polymethylsiloxane surfactant 0.04

Toluene diisocyanate (80/20 mixture of 2,4- /2.6-isomers) I05 index Theabove mixture, including the 7.5 grams of the product of Example 1, washand-mixed at room temperature and immediately poured into a squarealumi num mold which had been preheated to about 60C. Foaming took placeinstantaneously and was completed in about 2.5 minutes. After the lapseof minutes from the time the mixture was placed into the mold, the foamhad acquired a wholesome body which could be removed from the mold freeof surface defects. The foam was subjected to various tests in order todetermine its physical properties. The results of these tests areprovided in Table II below.

COMPARISON 7 mixture of 2,4/2,6-isomers) and of polyphenylenepolymethylene isocyanate sold commercially under the trade mark PAPI.Again the physical properties of this foam were tested and the resultsare given in Table II.

TABLE 11 Ex- Comamplc 6 parison 7 Core density (lbs. per cu.ft.) 2.5 2.6indentation load deflection(lbs.), per ASTM D-l564-64T a) at 2571deflection 38 34 b) at 6571 deflection 97 108 c) SAC fuctor(bI-a) 2.53.! Bull rebound. 7!. per ASTM D-l564-64T 54 54 Tensile strength(lbs.persq.in.) 17.8 21 Tear strength(lbs.per linear foot) 3.6 2.6

The data in Table II demonstrates the effectiveness of the curing agentof the invention as compared with a prior art curing agent. As shown,the invention foam and the prior foam are both high resilience withsubstantially comparable desirable properties. It is also to be notedthat the high resilence properties of the foam of the invention obtaineven though no polymeric isocyanate was used in making this foam asdistinguished from the prior art foam.

What is claimed is:

l. A composition of matter which is comprised of a combination of (a)bis(diisocyanatobenzyl)chlorobenzene and (b)diisocyanatophenylwchlorophenylmcthane in a weight ratio, (a):(b),ranging from about 15:85 to about 60:40, said combination being selectedfrom the group consisting of a combination of bis(2,4-diisocyanatobenzyl)chlorobenzene and 2,4- diisocyanatophenylchlorophenylmethane, a combina tion of bis(2,6diisocyanatobenzyl)-chlorobenzene and2,6-diisocyanatophenyl-chlorophenylmethane, a combination ofbis(2,5-diisocyanatobenzyl)-chlorobenzene and2,4-diisocyanatophenyl-chlorophenylmethane, a combination ofbis(3,5-diisocyanatobenzyl)-chlorobenzene and3,S-diisocyanatophenyl-chlorophenylmethane, and a mixture thereof.

2. A composition as claimed in claim 1 wherein said combination isselected from the group consisting of a combination ofbis(2,4-diisocyanatobenzyl)chlorobenzene and2,4-diisocyanatophenyl-chlorophenylmethane, a combination ofbis(2,6-diisocyanatobenzyl)- chlorobenzene and2,6-diisocyanatophenyl-chlorophenylmethane, and a mixture thereof.

3. The composition of claim 2 wherein said weight ratio ranges fromabout 25:75 to about 50:50.

4. A composition as claimed in claim 3 which is the product ofcondensing about 1.8-4 moles of monochlorobenzene per mole ofa-chloro-toluene diisocyanate, the latter being a mixture ofa-chloro-2.4-toluene diisocyanate and a-chloro-2,6-toluene diisocyanate.

1. A COMPOSITION OF MATTER WHICH IS COMPRISED OF A COMBINATION OF (A)BIS(DIISOCYANATOBENZYL)CHLOROBENZENE AND (B)DIISOCYANATOPHENYL-CHLOROPHENYL METHANE IN A WEIGHT RATIO, (A):(B),RANGING FROM ABOUT 15:85 TO ABOUT 60:40, SAID COMBINATION BEING SELECTEDFROM THE GROUP CONSISTING OF A COMBINATION OFBIS(2,4-DIISOCYANATOBENZYL)CHLOROBENZENE AND2,4DIISOCYANATOHENYL-CHLOROPHENYLMETHANE, A COMBINATION OFBIS(2,6-DIISOCYANATOBENZYL)-CHLOROBENZEND AND2,6DIISOCYANATOPHENYL-CHLOROPHENYLMETHANE, A COMBINATION OFBIS(2,5-DIISOCYANATOBENZYL)-CHLOROBENZENE AND2,4DIISOCYANATOPHENYL-CHLOROPHENYLMETHANE, A COMBINATION OFBIS(3,5-DIISOCYANATOBENZYL)-CHLOROBENZENE AND3,5DIISOCYANATOPHENYL-CHLOROPHNYLMETHANE, AND A MIXTURE THEREOF.
 2. Acomposition as claimed in claim 1 wherein said combination is selectedfrom the group consisting of a combination of bis(2,4-diisocyanatobenzyl)chlorobenzene and2,4-diisocyanatophenyl-chlorophenylmethane, a combination ofbis(2,6-diisocyanatobenzyl)chlorobenzene and2,6-diisocyanatophenyl-chlorophenylmethane, and a mixture thereof. 3.The composition of claim 2 wherein said weight ratio ranges from about25:75 to about 50:50.
 4. A composition as claimed in claim 3 which isthe product of condensing about 1.8-4 moles of monochlorobenzene permole of Alpha -chloro-toluene diisocyanate, the latter being a mixtureof Alpha -chloro-2,4-toluene diisocyanate and Alpha -chloro-2,6-toluenediisocyanate.